Overexpression of Thermoalkalophilic Lipase from Bacillus stearothermophilus L1 in Saccharomyces cerevisiae

• Published in: Journal of microbiology and biotechnology Vol. 13; no. 3; pp. 451 - 456
• Main Authors: Ahn, Jung-Oh, Jang, Hyung-Wook, Lee, Hong-Weon, Choi, Eui-Sung, Haam, Seung-Joo, Oh, Tae-Kwang, Jung, Joon-Ki
• Format: Journal Article
• Language: Korean
• Published: 한국미생물생명공학회 30-06-2003
• Subjects: Bacillus stearothermophilus L1; induction time; Saccharomyces cerevisiae; thermoalkalophilic lipase; induction time; thermoalkalophilic lipase; Bacillus stearothermophilus L1; Saccharomyces cerevisiae
• ISSN: 1017-7825; 1738-8872

An expression vector system was developed for the secretory production of recombinant Bacillus stearothermophilus L1 lipase in Saccharomyces cerevisiae. The mature L1 lipase gene was fused to ${\alpha}-amylase$ signal sequence from Aspergillus oryzae for the effective secretion into the culture broth and the expression was controlled under GAL10 (the gene coding UDP-galactose epimerase of S. cerevisiae) promoter. S. cerevisiae harboring the resulting plasmid successfully secreted L1 lipase into the culture broth. To examine an optimum condition for L1 lipase expression in the fed-batch culture, L1 lipase expression was induced at three different growth phases (early, mid, and late-exponential growth phases). Maximum product on of L1 lipase (1,254,000 U/l, corresponding to 0.65/1) was found when the culture was induced at an early growth phase. Secreted recombinant L1 lipase was purified only through CM-Sepharose chromatography, and the purified enzyme showed 1,963 U/mg of specific activity and thermoalkalophilic properties similar to those reported for the enzyme expressed in Escherichia coli.